Explosive stud with grooved, flexible guiding and retaining element



Sept. 30, 1958 H. BEHREND 2,853,914

EXPLOSIVE STUD WITH GROOVED, FLEXIBLE GUIDING AND RETAINING ELEMENT Filed Dec. 51, 1954 /NVE/Vf0p HERBE/Q T BEH/QE O A 770R NE Y United States Patent EXPLOSIVE STUD WITH GROOVED, FLEXIBLE GUIDING AND RETAINING ELEMENT Herbert Behrend, Dusseldorf-Unterrath, Germany Application December 31, 1954, Serial No. 479,180 In Germany March 30, 1950 Public Law 619, August 23, 1954 Patent expires March 30, 1970 2 Claims. (Cl. 85-10) The present invention relates to devices for driving steel bolts into construction elements, for instance into mason-work, concrete, figured iron, by means of a gun powder charge and in particular to such devices in which the detachable barrel has a bore of equal diameter throughout its entire length in order to receive the cartridge and the bolt, whereby the steel bolt and the cartridge form separate, individual units.

Such devices are known, yet they had the drawback that due to the one-sided guidance of the bolt at its headend, a predetermined and, thereby, smooth and nonobjectionable spot where the bolt entered could not be assured, unless the guide-enlargement disposed at the head-end of the steel bolt is particularly long. This arrangement brings about the disadvantage, however, that the guide-enlargement extending after the shot must be removed. On the other hand, the shorter the guideenlargement, the more diflicult is the linear guidance of the steel bolt.

In recognition of this drawback, it has been, therefore, also proposed before to provide two guidance disks on the head-end of the steel bolt, which disks were spaced apart a short distance, and in which arrangement the front disk was sheared ofi when the steel bolt hit the construction element. If the latter consisted of comparatively softer material, for instance mason-work or concrete, this structure led to a damage of the wall surface, provided there was a sufliciently large gun powder charge, while upon using a weak gun powder charge the front disk operated as limit in the penetration of the steel bolt.

It is, therefore, one object of the present invention to provide a device for driving steel bolts into construction elements, in which the steel bolt carries at its front end an individual holding and guiding member which has incisions at its outer edge, which holding and guiding member is provided in addition to the guide-enlargement provided at the rear end of the steel bolt, the double guidance of the steel bolt at its rear and front ends bringing about at first the advantage that an exactly central and liner guidance is achieved in each case, furthermore due to the now assured exactly perpendicular hit of the point of the bolt on the wall, an unobjectionable seat of the bolt without damage to the wall surface is achieved; and,

finally, gases advancing over the rear guide-enlargement may now escape through the incisions of the front holding and guiding member, thereby safely avoiding a tearing oif of the holding and guiding member due to the pressure of such gases and, thereby, an interference with the linear movement of the bolt may be safely avoided.

It is another object of the present invention to provide a device for driving steel bolts into construction elements in which the bolt and the cartridge of required predetermined length and charge, respectively, is inserted into the barrel as separate units and not, as previously used, as single unit. Aside from the required time loss and labor, the joined unit required a projection at the head end of the bolt, which extends from the bolt after hitting the wall and, thus, is undesirable. Due to theresiliency of the guide member mounted on the front joint of the steel bolt, no additional means is required to retain the bolt in the barrel, the guide member itself functioning as holding member.

With these and other objects in view, which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawing, in which:

Figure l is an axial section through the barrel and the bottom member of a known device with abolt having no additional guiding member; i

Fig. 2 is an axial section, similar to that of Fig. 1 through a known device in which the bolt carries a novel holding and guide member; and

Fig. 3 is an elevation of the bolt and guide member. I

Referring now to the drawings and in particular to Fig. 1, it will be seen that the shown device is known and is, as a matter of fact, an older construction, in'whicha cartridge holder 11 is provided between the barrel 1 and the breech block member 2, to which the barrel 1 is screwed, the cartridge holder 11 receiving the cartridge 5. The bolt 4, inserted into the bore 6 of the barrel 1, is secured in this structure in the bore 12 of a holding disk 12 by means of a projection 8 of the bolt 4.

Figure 1 shows a bolt immediately subsequent to its expulsion from the disk 12 upon explosion of the powder charge. Since only the head end 8 of the bolt 4 operates as guide in the barrel 1, the bolt 4 assumes an oblique position and thus does not hit the wall perpendicularly. In this manner bad shots cannot be avoided.

In order to eliminate the possibility of such a bad effect, the front portion of the bolt 4 (Figs. 2 and 3) carries, in accordance with the present invention, a guide member 9 of resilient material, which simultaneously functions as holding member to retain the bolt 4 in the boring 6 of the barrel 1.

The bolt 4 may be inserted through the front end of the barrel 1 or, upon unscrewing of the barrel 1, from the bottom member 2 the bolt may be inserted through its rear end together with the cartridge 5.

By this arrangement it is not necessary to keep the cartridge and bolt in stock as a single unit or to combine the two to a single unit before charging, whereby. the guiding and holding member 9 fixes the bolt 4 in the barrel 1 in the desired position.

The bolt 4 is thus, in accordance with the present invention, not limited to the insufiicient head 8 at the rear end as guide in the barrel 1, rather due to the double guides disposed at both ends of the bolt 4, the linear guidance of the latter is assured under all circumstances.

The incisions 10 provided in the guide member 9 operate as safety means against tearing off the guide member 9 from the bolt 4 due to powder gases passing the head portion 8, so that the safe guidance of the bolt 4 is assured.

It is to be understood that the present invention is not limited to bolt receiving devices having a barrel, the boring of which has equal diameter throughout its entire length. The present invention may be used also in connection with bolt receiving devices disclosed in Fig. 1 in which a special cartridge carrying case is provided to receive the cartridge. In this case, however, the holding disk 12 and also the projection 8' of the bolt 4 may be eliminated, though it is to be taken into consideration that cartridges of a predetermined length only can be used in such case.

While I have disclosed one embodiment of the present invention, it is to be understood that this embodiment is given by example only and not in a limiting sense, the

with the novel holding determined by the by its ejection through the bore of an explosively actuated driving device, said bolt comprising a front end portion, a rear end portion of a diameter smaller than that of said bore, and a shank portion disposed therebetween and of a smaller diameter than that of said rear end portion, the latter carrying a head of a length amounting to a short portion of the entire length of said bolt, so that there is danger of said bolt tilting in said bore, and said front end portion having lesser diameter than that of said rear end portion and carrying an elastic ring member having rearwardly projecting tongues adapted to engage resiliently the inner wall of said bore when inserted into the latter, and the rearends of said tongues being disposed on an imaginary circle having a diameter larger than that of said bore prior to the insertion of said bolt into said bore,

said ring member being adapted to operate as a holding and guiding member and to secure jointly with said head of said rear end portion the axial guidance of said bolt in the bore of said driving device, and said ring member having a plurality of incisions disposed peripherally 4 V spaced apart between each pair of said adjacent tongues, in order to provide a passageway for the explosive gases in forward direction.

2. The bolt, as set forth in claim 1, wherein said incisions are arranged axially along the periphery of said ring member.

References Cited in the file of this patent UNITED STATES PATENTS 1,656,333 Lund Jan. 17, 1928 2,115,028 Logan Apr. 26, 1938 2,308,006 Hendrickson Jan. 12, 1943 2,336,819 Turechek- Dec. 14, 1943 2,380,204 Turechek July 10, 1945 2,395,354 Temple Feb. 19, 1946 2,499,227 Miles Feb. 28, 1950 2,549,993 Temple Apr. 24, 1951 2,593,506 Wales Apr. 22, 1952 2,637,241 Webber May 5, 1953 2,676,508 Erickson Apr. 27, 1954 2,679,645 Erickson June 1, 1954 2,697,830

Erickson Dec. 28, 1954 

